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News - Week 23 - 2009
Influenza A(H1N1) - update 37
43 countries have officially reported 12
022 cases of influenza A(H1N1) infection, including 86 deaths. The breakdown of the number
of laboratory-confirmed cases by country is given in the following table and map.
Link
ps:......interessant is te horen van een
Mexicaan die ik vorige week sprak, dat deze 'griep' elk jaar voorkomt in
Mexico.......niets bijzonders. Snapt U het nog ? Dus alle Mexicanen worden door de 'foute
benaming' lichterlijk scheef aangekeken en alle varkenshouders. Misschien voortaan DIRECT
in de media het beestje de juiste naam geven ! Absoluut 'vingertje-wijzen' heeft
plaatsgevonden. Met welke reden ?
Ditta
Breast MRI Detects Additional
“Unsuspected” Cancers Not Seen on Mammography or Ultrasound
Nearly 20% of patients with recently diagnosed breast cancer had additional malignant
tumors found only by MRI, according to a study performed at Dartmouth Hitchcock Medical
Center. A total of 199 patients with newly diagnosed breast cancer underwent breast MRI.
“We found additional, unsuspected cancers in the ipsilateral breast (the one that had
already been diagnosed with cancer) in 16% of patients; we found cancers in the
contralateral breast (the one that had not been diagnosed with cancer) in 4% of
patients,” said Petra J. Lewis, MD, lead author of the study. “These patients
had already had bilateral mammography and these tumors had not been apparent on
mammography,” said Dr. Lewis. “The detection of an unsuspected tumor is
critical. These additional tumors in nearly a fifth of patients are tumors that can
potentially grow and not be diagnosed until they are much larger—affecting the health
and survival of the patients,” she said. “This study has been particularly
helpful to us as clinicians because it gives us data we can discuss with patients when
recommending breast MRI,” said Dr. Lewis.
Alzheimer's discovery could bring
early diagnosis, treatment closer
A discovery made by researchers at McGill University and the affiliated Lady Davis
Research Institute for Medical Research at Montreal's Jewish General Hospital offers new
hope for the early diagnosis and treatment of Alzheimer's disease. In a study published in
the Journal of Biological Chemistry on May 15, Dr. Hemant Paudel, his PhD student Dong Han
and postdoctoral fellows Hamid Qureshi and Yifan Lu, report that the addition of a single
phosphate to an amino acid in a key brain protein is a principal cause of Alzheimer's.
Identifying this phosphate, one of up to two-dozen such molecules, could make earlier
diagnosis of Alzheimer's possible and might, in the longer term, lead to the development
of drugs to block its onset. The crucial protein, called a tau protein, is a normal part
of the brain and central nervous system. But in Alzheimer's patients, tau proteins go out
of control and form tangles that, along with senile plaques, are the primary cause of the
degenerative disease. Several years ago, it was discovered that tau proteins in normal
brains contain only three to four attached phosphates, while abnormal tau in Alzheimer's
patients have anywhere from 21 to 25 additional phosphates. Paudel and his team have
discovered that it is the addition of a single phosphate to the Ser202 amino acid within
the tau brain protein that is the principal culprit responsible for Alzheimer's. "The
impact of this study is twofold," said Paudel, associate professor at McGill's Dept.
of Neurology and Neurosurgery, and Project Director at the Bloomfield Centre for Research
in Aging at the Lady Davis. "We can now do brain imaging at the earliest stages of
the disease. We don't have to look for many different tau phosphates, just this single
phosphate. The possibility of early diagnosis now exists. "Second, the enzyme which
puts this phosphate on the tau can be targeted by drugs, so therapies can be developed.
This discovery gives us, for the first time, a clear direction towards the early diagnosis
and treatment of Alzheimer's."
A novel marker of colorectal
carcinoma
The colorectal cancer is thought to be resulted from a combination of environmental
factors, diet, lifestyle, chronic inflammation and accumulation of specific genetic
alterations. The pathogenesis and development of colorectal cancer involve multi-genes and
multi-steps. TSPAN1 (GenBank Accession No. AF065388) is a new member of TM4SF located at
chromosome 1 p34.1. It encodes a 241 amino acid protein. TSPAN1 was reported as a
tumor-related gene recently. A research team led by Dr Jian-Wei Zhu from Nantong
University, China, investigated the association between TSPAN1 and human colorectal
adenocarcinoma. Their study will be published on May 14, 2009 in the World Journal of
Gastroenterology In this study, total RNA was extracted in 20 human adenocarcinoma tissues
for TSPAN1 mRNA assay by RT-PCR. Eighty-eight specimens of human colorectal adenocarcinoma
were surgically removed. TSPAN1 protein levels in cancer tissues were determined by
immunohistochemistry using a polyclonal antibody against self-prepared TSPAN1. The
correlation between TSPAN1 expression and the clinicopathological factors and the overall
survival rate was analyzed by univariate and multivariate assay.
Is there any association between
COX2 and colon cancer?
Non-steroidal anti-inflammatory drugs (NSAIDs), which are known to reduce the risk of
colon cancer, act directly on cyclooxygenase-2 (COX2) and reduce its activity. Population
studies have found an association of inherited variations in the COX2 gene with colon
cancer risk, but others were unable to replicate this finding. Similarly, variations in
the uridine diphosphate glucuronosyltransferase 1A6 (UGT1A6) gene, which is also known to
be key in the metabolism of NSAIDs, have been shown to modify the effect of NSAIDs on
developing colon polyps, a precursor of colon cancer, but these modifications of NSAID
effects have not been observed in risk of colon cancer. A research article to be published
on May 14, 2009 in the World Journal of Gastroenterology addresses this question. The
research team led by Dr. Li from Case Western Reserve University examined the association
of variants of the COX2 and UGT1A6 genes, and their interaction with NSAID consumption, on
risk of colon cancer in attempt to more fully understand the relationship between genetic
variation and the protective effect of NSAIDs on colon cancer risk. They found that no
single nucleotide polymorphisms (SNPs) in either gene were individually statistically
significantly associated with colon cancer, nor did they statistically significantly
change the protective effect of NSAID consumption. Like others, the authors were unable to
replicate the association of variants in the COX2 gene with colon cancer risk (P >
0.05), and they did not observe that these variants modify the protective effect of NSAIDs
(P > 0.05). Their study does not support a role of COX2 and UGT1A6 genetic variations
in the development of colon cancer.
Irradiated food causes
demyelinating neurological disorder in cats
Scientists studying a mysterious neurological affliction in pregnant cats that have been
fed irradiated food have discovered a surprising ability of the central nervous system to
repair itself and restore functionwhen placed back on a normal diet. In a study published
in the Proceedings of the National Academy of Sciences, a team of researchers from the
University of Wisconsin-Madison reports that the restoration in cats ofmyelin a fatty
insulator of nerve fibers that degrades in a host of human central nervous system
disorders, the most common of which is multiple sclerosis can lead to functional recovery.
The fundamental point of the study is that it proves unequivocally that extensive
remyelination can lead to recovery from a severe neurological disorder, says Ian Duncan,
the UW-Madison neuroscientistwho led the research. It indicates the profound ability of
the central nervous system to repair itself.
La Jolla Institute unlocks mystery
of potentially fatal reaction to smallpox vaccine
Researchers from the La Jolla Institute for Allergy & Immunology have pinpointed the
cellular defect that increases the likelihood, among eczema sufferers, of developing
eczema vaccinatum, a severe and potentially fatal reaction to the smallpox vaccine. The
research, conducted in mouse models, was funded under a special research network created
by the National Institutes of Health in 2004. The network is working toward the
development of a new smallpox vaccine that could be administered to the millions of
Americans who suffer from atopic dermatitis, a chronic, itchy skin condition commonly
referred to as eczema. The La Jolla Institute's Toshiaki and Yuko Kawakami, M.D.s,
Ph.D.s., a husband and wife scientific team, led the research group which found that
activity levels of Natural Killer (NK) cells played a pivotal role in the development of
eczema vaccinatum in the mice. The activity of the NK cells, which are disease fighting
cells of the immune system, was significantly lower in the mice that developed eczema
vaccinatum than in normal mice that also received the smallpox vaccine. This knowledge
opens the door to one day developing therapies that could potentially boost NK cell
activity in eczema sufferers. "Since atopic dermatitis affects as many as 17 percent
of children in the U. S. and since eczema vaccinatum carries a fatality rate of 5-10
percent, therapies that prevent or treat eczema vaccinatum successfully are crucial should
the need for mass vaccination against smallpox arise in response to bioterrorism,"
said Harvard pediatrics professor Raif S. Geha, M.D., chief of immunology at Boston
Children's Hospital and a principal investigator in the NIH funded network investigating
eczema vaccinatum. "The discovery of the Kawakami team, who are participants in the
NIH network, is an important step towards this goal."People with active atopic
dermatitis (eczema), or who have outgrown atopic dermatitis, and the people they live with
currently cannot receive smallpox vaccinations because of the risk of eczema vaccinatum.
While uncommon, eczema vaccinatum can develop when atopic dermatitis patients are given
the smallpox vaccine or come into close personal contact with people who recently received
the vaccine. It is estimated that a significant portion of the U.S. population is
currently not eligible for smallpox vaccination. "This discovery answers an important
question that has long eluded the scientific community, "why people with atopic
dermatitis were susceptible to developing eczema vaccinatum upon receiving the smallpox
vaccine, while the general population was not," said Mitchell Kronenberg, the La
Jolla Institute's president & scientific director. "It marks a significant
advance toward the goal of ensuring that everyone can one day be protected against the
smallpox virus."
Immune genes adapt to parasites
Thank parasites for making some of our immune proteins into the inflammatory defenders
they are today, according to a population genetics study that will appear in the June 8
issue of the Journal of Experimental Medicine (online May 25). The study, conducted by a
team of researchers in Italy, also suggests that you might blame parasites for sculpting
some of those genes into risk factors for intestinal disorders. Parasite-driven selection
leaves a footprint on our DNA in the form of mutations known as "single nucleotide
polymorphisms" (SNPs). Making sure that genetic variation (in the form of multiple
SNPs) is maintained within certain immune genes over time helps ensure that the host can
fend off different infections in different environments. In the new study, Matteo
Fumagalli and colleagues sift through 1,052 SNPs in genes that code for immune proteins
called interleukins from roughly 1000 people worldwide. Of 91 genes assessed, 44 bore
signatures of evolutionary selection, meaning that the genetic variation was neither due
to chance nor to the migration of populations over time. And some of that variation
correlated with the diversity of parasites that live alongside humans. The data suggests
that having lots of different parasites around has shaped the evolution of our interleukin
genes. In general, parasitic worms appear to have had a more powerful influence on certain
interleukin genes than smaller microbes such as viruses, bacteria, and fungi. That isn't
surprising, says senior author Manuela Sironi, because worms typically evolve slower than
bacteria or viruses, giving their human hosts time to adapt in response. Some of the genes
that were shaped by worm diversity made perfect sense, as the proteins they encode help
generate the precise type of immune response required to rid the body of worms. Other
genes, however, seemed to be influenced more by the diversity of viruses, bacteria, and
fungi than by that of worms. SNPs in some of these genes are known risk alleles for
inflammatory bowel diseases, such as Crohn's and celiac disease. These "risky"
alleles were probably maintained during evolution because they promote the kind of immune
response needed to fend off viruses and bacteria. But this type of response also
contributes to inflammatory bowel diseases.
Identification of genetic variants
affecting age at menopause could help improve fertility treatment
For the first time, scientists have been able to identify genetic factors that influence
the age at which natural menopause occurs in women. Ms Lisette Stolk, a researcher from
Erasmus MC, Rotterdam, The Netherlands, told the annual conference of the European Society
of Human Genetics today ( Monday 25 May) that a greater understanding of the factors
influencing age at menopause might eventually help to improve the clinical treatment of
infertile women. Ms Stolk and her team performed a Genome-Wide Association Study (GWAS) in
10,339 menopausal women. The data analysed were taken from 9 different studies undertaken
in The Netherlands (the Rotterdam Study 1 and 2), the UK (the TwinsUK study), USA (the
Framingham study, the Cardiovascular Health Study, the ARIC study, the HAPI Heart Study),
Iceland (AGES-Reykjavik) and Italy (the InCHIANTI study). The scientists found 20 single
nucleotide polymorphisms (SNPs) in four different places on chromosomes 19 and 20. SNPs
are common genetic variants that influence how humans look, behave, develop disease or
react to pathogens. In genetics they are used to compare regions of the genome between
different groups of individuals and to identify those regions that are associated with a
particular disease or characteristic. The SNPs the researchers found had not been
identified before, and the part of the body where they might have an effect has yet to be
identified, though the researchers speculate that this is likely to be in the ovaries or
brain. "We found that the 20 SNPs were all related to a slightly earlier
menopause", said Ms Stolk, "and women who had one of them experienced menopause
nearly a year earlier than others. We know that ten years before menopause women are much
less fertile, and five years before many are infertile. In Western countries, where women
tend to have children later in life and closer to menopause, age at menopause can be an
important factor in whether or not a particular woman is able to become a mother." In
addition to its effect on fertility, earlier menopause has other deleterious effects on
women such as an increased risk for osteoporosis, osteoarthritis and cardiovascular
disease, while it has a protective effect on the risk of breast cancer. The age of
menopause varies greatly among Caucasian women, ranging between 40 and 60 year of age,
with an average at around 50. The reasons for this variation are unknown, but there is
evidence from studies of twins that this could be due to inheritable genetic factors.
However, until now, GWAS had not been used to study the effect of genetic variants on age
at menopause.
Scientists find shared genetic link
between the dental disease periodontitis and heart attack
The relationship between the dental disease periodontitis and coronary heart disease (CHD)
has been known for several years. Although a genetic link seemed likely, until now its
existence was uncertain. Now, for the first time, scientists have discovered a genetic
relationship between the two conditions, a researcher told the annual conference of the
European Society of Human Genetics today (Monday 25 May). Dr. Arne Schaefer, of the
Institute for Clinical Molecular Biology, University of Kiel, Germany, said that his team
had discovered a genetic variant situated on chromosome 9 which was shared between the two
diseases. "We studied a genetic locus on chromosome 9p21.3 that had previously been
identified to be associated with myocardial infarction, in a group of 151 patients
suffering from the most aggressive, early-onset forms of periodontitis, and a group of
1097 CHD patients who had already had a heart attack. The genetic variation associated
with the clinical pictures of both diseases was identical," he said. The scientists
went on to verify the association in further groups of 1100 CHD patients and 180
periodontitis patients. "We found that the genetic risk variant is located in a
genetic region that codes for an antisense DNA called ANRIL", said Dr. Schaefer,
"and that it is identical for both diseases." When a gene is ready to produce a
protein, the two strands of DNA in the gene unravel. One strand produces messenger RNA,
and will express a protein. Antisense RNA is complementary to the mRNA, and is often
carried by the reverse strand, the 'anti-sense' strand of the DNA double helix. This
strand does not encode for a protein, but can bind specifically to the messenger RNA to
form a duplex. Through this binding, the antisense strand inhibits the protein expression
of the mRNA . Coronary heart disease is the leading cause of death worldwide, and
periodontitis, which leads to the loss of connective tissue and the bone support of teeth,
is the major cause of tooth loss in adults over 40 years. Periodontitis is very common,
and around 90% of people aged over 60 suffer from it. Research has already shown a genetic
basis for both diseases.
Sugar - Can we go without it?
1. Sugar can suppress the immune system
2. Sugar upsets the mineral relationships in the body
3. Sugar can cause hyperactivity, anxiety, difficulty concentrating,
and crankiness in children
4. Sugar can produce a significant rise in triglycerides
5. Sugar contributes to the reduction in defense against bacterial infection (infectious
diseases)
6. Sugar causes a loss of tissue elasticity and function, the more sugar you eat the more
elasticity and function you loose
7. Sugar reduces high density lipoproteins
8. Sugar leads to chromium deficiency
9. Sugar leads to cancer of the breast, ovaries, prostrate, and rectum
10. Sugar can increase fasting levels of glucose
Lees verder
Lisa Bakker
The evolution of gene regulation
Even microbes are governed by the principle of supply and demand – at least at the
genetic level. Not all of their gene products, the blueprints for proteins, are required
at all times. That means most of their genes only become active when they are needed, as
is the case in higher organisms. In the simplest case, a transcription factor will
activate the gene in question at the right time. Genes that are regulated in a somewhat
more complex manner, on the other hand, are kept inactive by a repressor that is removed
only when the gene is needed. Which of these two regulation mechanisms will develop is a
question of demand, along the lines of a "use-it-or-lose-it" principle: if genes
are frequently active, then, as a rule, they will be directly induced. Genes that encode
more rarely used proteins, on the other hand, tend to be kept inactive by repressors. LMU
physicist Ulrich Gerland and Professor Terence Hwa of the University of California have
now demonstrated using computer simulations and theoretical analyses that another –
indeed opposing – principle also comes into play: "wear-and-tear".
According to this principle, direct activation can lead to harmful changes. "Which of
the two principles prevails depends on evolutionary criteria such as the population size
and the periods over which environmental changes take place," says Gerland. "Our
study may serve as a useful basis for more detailed studies of the evolution of regulatory
systems." (PNAS Early Edition, 22 Mai 2009) Up until the middle of the 20th century,
biochemists spent most of their efforts studying metabolism, i.e. obtaining energy from
food. Less importance was given to the – technically inexplicable – question of
how proteins were regulated as a response to internal and external signals. The biology of
regulation only came into its own as an independent research field when technical progress
opened the window to scientific analysis of DNA, the carrier of genetic traits, and to the
synthesis of proteins, the most important functional elements of the cell. It quickly
became clear that complex and diverse regulation mechanisms adapted the genetic activity
of cells to internal and external conditions – even in microorganisms. It is known,
for example, that the intestinal bacterium Escherichia coli in the digestive tract of
young mammals can break down lactose, the sugar abundant in mother's milk. To do this, the
bacterium produces the enzyme lactase – but only if lactose is actually present. Most
of the time, however, lactose is not present. At these times, the gene that encodes the
lactase enzyme is blocked by a repressor. Only one key fits the lock to this protein, to
detach the repressor from the lactase gene: a lactose molecule, as a single, unmistakable
sign that this sugar is present and now available as food. Other genes, however, are
regulated without the use of repressors: these genes are directly activated by a
transcription factor that binds to them.
The neurobiology of musicality
related to the intrinsic attachment behavior?
In the study of University of Helsinki and Sibelius Academy, Helsinki, the neurobiological
basis of music in human evolution and communication was evaluated using candidate genes
associated in the earlier studies with social bonding and cognitive functions. The data
consisted of 343 family members from 19 Finnish families with at least some professional
musicians and/or active amateurs. The musical aptitude was assessed using three music
tests: the auditory structuring ability test (Karma Music test) and Carl Seashore's pitch
and time discrimination subtests. Additionally participants filled in an extensive
web-based self-report questionnaire and blood samples were collected from the study
subjects over 12 years of age. One part of the questionnaire was devised to chart the
participants creative functions in music –composing, improvising and arranging of
music. In the study high music test scores were significantly associated with creative
functions in music (p< .0001), suggesting composing, improvising and arranging music
demands musical aptitude. Creativity is a multifactorial genetic trait involving a complex
network made up of a number of genes and environment. Here was shown for the first time
that the creative functions in music have a strong genetic component (h2 =.84; composing
h2 =.40; arranging h2 =.46; improvising h2 = .62) in Finnish multigenerational families.
Additionally the heritability estimates of the musical aptitude were remarkable.
Pediatrician creates easier way to
identify kids' high BP
Pediatricians now have a new and simple way to diagnose a serious problem facing our
nation's children – thanks to David Kaelber, M.D., Ph.D., M.P.H., MetroHealth System
pediatrician, internist, and chief medical informatics officer and Case Western Reserve
University School of Medicine researcher and faculty member. Nearly 75% of cases of
hypertension and 90% of cases of prehypertension in children and adolescents go
undiagnosed. These troubling statistics were documented in previously published research
by Dr. Kaelber. From this research, Dr. Kaelber and fellow researchers felt that one of
the main reasons for the under-diagnosis may be due to the complex chart currently used to
help physicians and medical personnel identify high blood pressure in children. So Dr.
Kaelber's team simplified the chart – focusing solely on a child's age and gender
– eliminating the need for a height percentile and reducing the number of values in
the blood pressure table from 476 to just 64. The revised chart and accompanying
description are published in the June issue of the journal Pediatrics. The American
Academy of Pediatrics and the American Heart Association recommend that blood pressure
checks be done at all pediatric visits for health care (including dental and optometric
appointments) for children ages 3 to 18. The current standard chart used by healthcare
providers to evaluate pediatric blood pressure is from the National Heart, Lung, and Blood
Institute and includes hundreds of normal and abnormal blood pressure values. In order to
differentiate between normal and abnormal readings, providers need to, not only remember
the variety of blood pressure ranges, but also know the child's height percentile –
which can be difficult to verify, especially in non-primary care settings.
Comprehensive cardiogenetic testing
for families of sudden unexplained death victims can save lives
Relatives of a young person who dies suddenly should always be referred for cardiological
and genetic examination in order to identify if they too are at risk of sudden death, a
scientist told the annual conference of the European Society of Human Genetics today
(Tuesday 26 May). Dr. Christian van der Werf, a research fellow at the Department of
Cardiogenetics, Academic Medical Centre, Amsterdam, The Netherlands said that, although
his team's research showed that inherited heart disease was present in over 30% of the
families of sudden unexplained death (SUD) victims, the majority of such relatives were
currently not being referred for examination. When an individual aged 1-50 years dies
suddenly, autopsy reveals an inheritable heart disease in the majority of the victims. But
in approximately 20% autopsy does not reveal the cause of death. "We thought that
cardiological and genetic examination of surviving first degree relatives of these SUD
patients might reveal an inherited heart disease", said Dr. van der Werf. In the
largest such study to date, the team looked at the outcome of first degree relative
screening in 127 families who had suffered an SUD and where either there had been no
autopsy (53.8%), or the autopsy did not reveal a cause of death. The average age at death
of the SUD victims was only 29.8 years old. The initial examination of the relatives
consisted of taking personal and family medical history and a resting ECG. A second
cardiac autopsy of the SUD victim was undertaken if tissue had been stored and was
available. Additional cardiological examinations of the relatives were performed where
necessary. Genetic analysis of the associated candidate gene(s) was performed in material
obtained from the deceased person or in those relatives who showed clinical abnormalities.
The researchers found inherited heart disease in 36, or 32% of the families. These results
meant that doctors were able to treat affected relatives and try to prevent their
succumbing to sudden cardiac death. "The scale of heart disease that we found in such
families underlines the necessity for general practitioners to refer first degree
relatives of SUD victims to a specialised cardiogenetics department as soon as
possible", said Dr. van der Werf. "Currently we estimate that only 10% of SUD
families are being examined for inherited heart conditions.
A new mouse model provides insight
into genetic neurological disorders
Neurosensory diseases are difficult to model in mice because their symptoms are complex
and diverse. The genetic causes identified are often lethal when transferred to a mouse.
The lack of animal models slows progress in understanding and treating the diseases. By
strategically altering a protein-making molecule, a mouse was made to help understand
nervous system diseases that impair feeling and cause paralysis of the arms and legs in
humans. Scientists have created a mouse to help understand human neuronal diseases that
impair a patient's ability to feel and to move their arms and legs. By strategically
altering a protein-making molecule, a mouse was made with symptoms similar to the nervous
system diseases, Charcot-Marie-Tooth (CMT) and hereditary motor neuropathy (HMN). In CMT
and HMN, neurons that signal and maintain muscle cells become defective, which causes
weakening and loss of muscle that is significant enough in some cases to lead to death.
The symptoms become progressively worse over time and no effective treatments or cures
exist for these diseases. Researchers came together from the University College London
(UCL), the Medical Research Centre (MRC) Harwell, the University of Oxford, and the
University of London in England, Vrije University in The Netherlands and Jackson
Laboratories in the US to make a genetic change in mice that has been associated with CMT
and HMN diseases in people. Neurosensory diseases are difficult to model in mice because
they involve symptoms that are complex and diverse. These diseases are passed from parents
to their children but the genetic causes identified are often lethal when transferred to a
mouse. The lack of animal models slows progress in understanding and treating the
diseases.
What is the function of lymph
nodes?
If we imagine our immune system to be a police force for our bodies, then previous work
has suggested that the Lymph nodes would be the best candidate structures within the body
to act as police stations – the regions in which the immune response is organised.
However, Prof. Burkhard Becher, University of Zurich, suggests in a new paper –
published in this week's issue of PLoS Biology – that lymph nodes are not essential
in the mouse in marshalling T-cells (a main immune foot soldier) to respond to a breach of
the skin barrier. This result is both surprising in itself, and suggests a novel function
for the liver as an alternate site for T-cell activation. When a child falls off its bike
and scratches its skin, the body responds via the immune system. Scavenger cells at the
site of the wound pick up antigens –tiny particles derived from invading
microorganisms and dirt that the body will recognize as foreign. These antigens are
delivered to the nearest lymph node. T and B cells (immune cells) carrying the matching
antigen-receptors on their surface will be stimulated by the concentrated antigen now
present in these lymph nodes. T cells will then go on and orchestrate the defensive
response against the invaders, whereas B cells will transform into antibody-producing
cells flooding the body with antibodies which act against the hostile microorganisms. Mice
that lack lymph nodes due to a genetic mutation (alymphoplasia) are severely
immuno-compromised and struggle in fighting infections and tumors. New work by Melanie
Greter, Janin Hofmann and Burkhard Becher from the Institute of experimental Immunology at
the University of Zurich reports that the immunodeficiency associated with alymphoplasia
is not due to the lack of lymph nodes, but caused by the genetic lesion on immune cells
themselves. The new paper shows that in the mouse T cell function is unperturbed in the
absence of lymph nodes, whereas B cell activation and antibody secretion is strongly
affected. That T cell responses can be launched outside of lymph nodes is highly
surprising, because this means that T cells can encounter antigens elsewhere in order to
become activated. By tracing the migration of fluorescent particles from the site of
antigen invasion (i.e. the wound) the scientists discovered that the liver could serve as
a surrogate structure for T cell activation. During embryonic development, the liver is
the first organ to provide us with blood and immune cells. Apparently, at least in the
mouse the liver continues to serve as an "immune organ" even during adulthood.
This work suggests an explanation for the curious fact that patients receiving a liver
transplant sometimes inherit the donor's allergies and immune repertoire, so in keeping
with the idea that donor immune information is being transplanted. It also suggests that
the liver as an immune organ is an evolutionary remnant from the time before lymph nodes
developed in higher birds and mammals. Cold-blooded vertebrates have functioning T and B
cells but no lymph nodes. The main achievement of the development of lymph nodes in
mammals is a drastic improvement for the production of better antibodies. T cells on the
other hand have not changed their function much during evolution and the work by the
Zurich group finally provides solid evidence for the versatility and promiscuity of this
cell type.
New therapy enlists immune system
to boost cure rate in a childhood cancer
A multicenter research team has announced encouraging results for an experimental therapy
using elements of the body's immune system to improve cure rates for children with
neuroblastoma, a challenging cancer of the nervous system. John M. Maris, M.D., chief of
Oncology at The Children's Hospital of Philadelphia, co-authored the phase 3 clinical
trial, which was led by Alice Yu, M.D., Ph.D., of the University of California, San Diego.
Maris chairs the committee supervising the trial for the Children's Oncology Group, a
cooperative organization that pools resources from leading medical centers to study and
devise new treatments for pediatric cancers. Neuroblastoma, a cancer of the peripheral
nervous system, usually appears as a solid tumor in the chest or abdomen. Neuroblastoma
accounts for 7 percent of all childhood cancers, but due to its often aggressive nature,
causes 15 percent of all childhood cancer deaths. Yu will present the neuroblastoma study
results on June 2 at the annual meeting of the American Society of Clinical Oncology
(ASCO) in Orlando, Fla. In advance of the meeting, ASCO published the findings online on
May 14. Maris explained that immunotherapy for cancer involves triggering the body's
immune system to attack cancer cells. Monoclonal antibodies are molecules customized to
target particular cancers, while cytokines are naturally occurring signaling proteins that
regulate the body's immune responses.
Mayo Researchers Help Discover
Genetic Cause for Primary Biliary Cirrhosis
Researchers have discovered a novel molecular path that predisposes patients to develop
primary biliary cirrhosis, a disease that mainly affects women and slowly destroys their
livers. Primary biliary cirrhosis has no known cause. The finding, significant because it
is a first step toward developing a targeted treatment and a cure, will be published in
the June 11, 2009, issue of the New England Journal of Medicine. "Now that we better
understand the molecular basis of primary biliary cirrhosis, we can look for ways to
specifically fix those elements," says Konstantinos Lazaridis, M.D., a Mayo Clinic
hepatologist and a senior researcher in the study.
Sea-level rise may pose greatest
threat to Northeast US, Canada
The melting of the Greenland Ice Sheet this century may drive more water than previously
thought toward the already threatened coastlines of New York, Boston, Halifax and other
cities in the northeastern United States and Canada, according to new research. Results of
the study are being published this week in Geophysical Research Letters. They suggest that
moderate to high rates of ice melt from Greenland may shift ocean circulation by about
2100, causing sea levels off the northeast coast of North America to rise by about 30 to
51 centimeters (12 to 20 inches) more than other coastal areas. The research builds on
recent reports that have found that sea level rise could adversely affect North America,
and its findings suggest that the situation is even more urgent than previously believed.
"If the Greenland melt continues to accelerate, we could see significant impacts this
century on the northeast U.S. coast from the resulting sea level rise," says
scientist Aixue Hu, the paper's lead author. Hu is at the National Center for Atmospheric
Research (NCAR) in Boulder, Colo. "Major northeastern cities are directly in the path
of the greatest rise." A study in Nature Geoscience in March warned that warmer water
temperatures could shift ocean currents in a way that would raise sea levels off the
Northeast by about eight inches more than the average global sea level rise that is
expected with global warming.
Why Some Prostate Cancer Returns
The majority of men who receive one of the standard treatments for localized prostate
cancer - surgery or radiation therapy - have an excellent outcome. But for the small group
whose prostate cancer returns, a new study offers insight as to why treatment isn't
effective. The study - a collaboration between researchers at the Josephine Ford Cancer
Center at Henry Ford Hospital and Fox Chase Cancer Center - shows that men with a low
oxygen supply to their tumor have a higher chance of the prostate cancer returning, as
found by increasing prostate-specific antigen (PSA) levels following treatment.
"After several years of research, we were able to show that low levels of oxygen to
the tumor are highly related to a patient's outcome. Those with lower oxygen levels to the
prostate cancer did not respond as well to radiation therapy, and the cancer returned more
often," says Benjamin Movsas, M.D., senior study author and chair of the Department
of Radiation Oncology at Henry Ford Hospital. Moreover, recent studies suggest the same
finding also appears to apply to patients treated with surgery.
History of hyperactivity off-base,
says researcher
A Canadian researcher working in the U.K. says doctors, authors and educators are doing
hyperactive children a disservice by claiming that hyperactivity as we understand it today
has always existed. Matthew Smith says not only is that notion wrong, it misleads
patients, their parents and their physicians. Smith, who is from Edmonton, is finishing up
his PhD at the Centre for Medical History at the University of Exeter. Hyperactivity
disorder, or ADHD, is currently the most commonly diagnosed childhood psychiatric
disorder, says Smith, and millions of children are prescribed drugs such as Ritalin to
treat it. Yet prior to the 1950s, it was clinically and culturally insignificant. He
argues in a paper presented at the Congress for the Humanities and Social Sciences taking
place at Ottawa's Carleton University this week, that hyperactivity disorder as we
understand it today is a modern construct that was first described as a disorder in
1957.Before that, Smith says hyperactive behaviour existed – but it wasn't always
thought of as a disorder or pathology worth treating. However, Smith says many today
assert that hyperactivity is a universal phenomenon, and say evidence of hyperactivity can
be seen in historical figures such as Mozart or Einstein. Smith argues that hyperactivity
as we understand it is rooted in social, cultural, political and economic changes of the
last half century.
Weed resistance to glyphosate in
genetically modified soybean cultivation in Argentina
The article written by Rosa Binimelis, Walter Pengue and Iliana Monterroso, is the product
of collaborative work among the Autonomous University of Barcelona, University of Buenos
Aires and the Latin American Faculty of Social Sciences in Guatemala. The article
describes the geographical advance of the invasion beyond the Pampas, it reviews the
environmental history of the invasion process to discuss the major drivers and pressures
in the context of the changes of the agriculture of Argentina in the last twenty years. It
discusses how the process of agricultural modernization in Argentina has resulted in the
intensification of crops via sophisticated technological packages including an increase
use of inputs and the adoption of GMOs. In 2007, the historical records for soybean yield
and price in Argentina were reached, to some extent due to the sharply escalating biofuels
demand. Nevertheless, if more genetic-resistant weeds appear, the benefits derived from
the model could be lost. Results highlight the socio-economic impacts and responses
associated with invasive species affecting agro-biodiversity. They indicate that no
preventive strategies are deployed against the invasion of johnsongrass. Instead, the
reactive measures are based on "gene-stacking" that allows the use of still more
glyphosate or new combinations of herbicides, thus combining the pesticide treadmill with
a novel "transgenic treadmill". The article also evidences the need to further
analyze how policies in other regions affect the management of a biodiversity issue, for
instance the EU Directive 2003/30/EC (8 May 2003) on the promotion of the use of biofuels
for transport. Therefore, this study has policy relevance also for the European Union. The
EU is a large importer of soybeans from Argentina. European awareness of the local impacts
of imported soybeans (as feedstuffs and/or agro-fuels) should not focus only on
deforestation. It should take the findings of this study into account.
Brain activation can predict the
strategies people use to make risky decisions
Watching people's brains in real time as they handle a set of decision-making problems can
reveal how different each person's strategy can be, according to neuroscientists at the
Duke University Medical Center. "People in our study, like the population at large,
differed in the strategies they use to make economic decisions," said Scott Huettel,
Ph.D., co-director of the Duke Center for Neuroeconomic Studies and senior author of the
study published in Neuron online on May 27. "What sort of strategy people tended to
use could be predicted, surprisingly, by how their brain responded to rewards: if there
were large responses to monetary reward in a brain area called the ventral striatum, that
person tended to simplify decision problems to only consider winning or losing."
"Using studies like this to build a better understanding of how our brains represent
our decision strategies may someday allow researchers to use someone's personal traits
– say, an adolescent with high impulsivity, but ongoing depression – to predict
the decisions that he or she will make," Huettel said. "This could lead to many
real-world benefits: designing more effective interventions or creating more useful
educational material." Twenty-three participants were scanned using functional
magnetic resonance imaging (fMRI) which reveals real-time changes in brain function as
they evaluated complex multi-outcome lotteries. The problems involved real monetary gains
and losses – something akin to the universe of factors that someone buying a car must
consider, for example. When faced with each problem, the participant chose among ways to
improve their lottery chances, such as reducing the worst possible loss. This study was a
collaboration between neuroscientists and decision making experts at the Fuqua School of
Business at Duke.
Carbohydrate Restriction May Slow
Prostate Tumor Growth
Restricting carbohydrates, regardless of weight loss, appears to slow the growth of
prostate tumors, according to an animal study being published this week by researchers in
the Duke Prostate Center. "Previous work here and elsewhere has shown that a diet
light in carbohydrates could slow tumor growth, but the animals in those studies also lost
weight, and because we know that weight loss can restrict the amount of energy feeding
tumors, we weren't able to tell just how big an impact the pure carbohydrate restriction
was having, until now," said Stephen Freedland, MD, a urologist in the Duke Prostate
Center and lead investigator on this study. The researchers believe that insulin and
insulin-like growth factor contribute to the growth and proliferation of prostate cancer,
and that a diet devoid of carbohydrates lowers serum insulin levels in the bodies of the
mice, thereby slowing tumor growth, Freedland said.
Americans choose media messages
that agree with their views
A new study provides some of the strongest evidence to date that Americans prefer to read
political articles that agree with the opinions they already hold. Researchers found that
people spent 36 percent more time reading articles that agreed with their point of view
than they did reading text that challenged their opinions.Even when they did read articles
that countered their views, participants almost always balanced that with reading others
that confirmed their opinions. The study is important because it is one of the first to
record what people actually read and link these findings to their views on the same
topics.
Cottonseed-Based Drug Shows Promise
Treating Severe Brain Cancer
An experimental drug derived from cottonseeds shows promise in treating the recurrence of
glioblastoma multiforme, widely considered the most lethal brain cancer, said researchers
at the University of Alabama at Birmingham (UAB). The new results are from a Phase II
clinical trial of AT-101, a pill manufactured from a potent compound in cottonseeds that
overcomes the abnormal growth patterns of tumor cells. This cottonseed-based agent must be
properly dosed and monitored by physicians. In clinical tests, AT-101 halted the cancer's
progression in many of the 56 patients, said John Fiveash, M.D., an associate professor in
the UAB Department of Radiation Oncology and the lead researcher on the new study. Despite
undergoing other treatments, including surgery, chemotherapy and radiation, the trial
patients' brain cancer had begun to grow again prior to starting AT-101 treatments. The
trial-monitored patients took only AT-101 daily for three out of four weeks. Glioblastomas
are more common in adults and are considered fast-growing brain tumors that are very
difficult to treat, Fiveash said.
Is cherry juice a new 'sports
drink?'
Drinking cherry juice could help ease the pain for people who run, according to new
research from Oregon Health & Science University presented at the American College of
Sports Medicine Conference in Seattle, Wash. The study showed people who drank tart cherry
juice while training for a long distance run reported significantly less pain after
exercise than those who didn't. Post-exercise pain can often indicate muscle damage or
debilitating injuries. In the study of sixty healthy adults aged 18-50 years, those who
drank 10.5 ounces cherry juice (CHERRish 100% Montmorency cherry juice) twice a day for
seven days prior to and on the day of a long-distance relay had significantly less muscle
pain following the race than those who drank another fruit juice beverage. On a scale from
0 to 10, the runners who drank cherry juice as their "sports drink" had a 2
point lower self-reported pain level at the completion of the race, a clinically
significant difference. While more research is needed to fully understand the effects of
tart cherry juice, researchers say the early finding indicate cherries may work like
common medications used by runners to alleviate post-exercise inflammation. "For most
runners, post-race treatment consists of RICE (rest, ice, compression and elevation) and
traditional NSAIDS (non-steroidal anti-inflammatory drugs)," said Kerry Kuehl, M.D.,
a sports medicine physician and principal study investigator. "But NSAIDS can have
adverse effects – negative effects you may be able to avoid by using a natural, whole
food alternative, like cherry juice, to reduce muscle inflammation before exercise."
The researchers suggest cherries' post-exercise benefits are likely because of the fruit's
natural anti-inflammation power – attributed to antioxidant compounds called
anthocyanins, which also give cherries their bright red color.
Dementia drugs may put some
patients at risk, Queen’s study shows
may be putting elderly Canadians at risk, says Queen's University Geriatrics professor
Sudeep Gill. Cholinesterase inhibitors (Aricept, Exelon and Reminyl) are often prescribed
for people with Alzheimer's disease and related dementias because they increase the level
of a chemical in the brain that seems to help memory. Although such drugs are known to
provoke slower heart rates and fainting episodes, the magnitude of these risks has not
been clear until now. "This is very troubling, because the drugs are marketed as
helping to preserve memory and improve function," says Dr. Gill, who is an Ontario
Ministry of Health and Long-term Care Career Scientist, working at Providence Care's St.
Mary's of the Lake Hospital in Kingston. "But for a subset of people, the effect
appears to be the exact opposite." In a large study using province-wide data, Dr.
Gill and his colleagues discovered that people who used cholinesterase inhibitors were
hospitalized for fainting almost twice as often as people with dementia who did not
receive these drugs. Experiencing a slowed heart-rate was 69 per cent more common amongst
cholinesterase inhibitor users. In addition, people taking the dementia drugs had a 49 per
cent increased chance of having permanent pacemakers implanted and an 18 per cent
increased risk of hip fractures.
Portable device can detect viruses
in minutes
University of Twente spin-off company develops spectacularly fast virus detector. Imagine
being able to detect in just a few minutes whether someone is infected with a virus. This
has now become a reality, thanks to a new ultra-sensitive detector that has been developed
by Ostendum, a spin-off company of the University of Twente. The company has just
completed the first prototype and expects to be able to introduce the first version of the
detector onto the market in late 2010. Not only does the detector carry out measurements
many times faster than do standard techniques, it is also portable, so it can be used
anywhere. Ostendum’s Aurel Ymeti (R&D director), Alma Dudia (Senior Researcher)
and Paul Nederkoorn (CEO) claim that if they had the right antibodies to the swine flu at
their disposal, they would be able to highlight the presence of the virus within five
minutes. In addition to viruses, the device is also able to pick up bacteria, proteins and
DNA molecules. Following the outbreak of swine flu, the issue of finding a means of
detecting quickly and simply whether someone is infected with a virus is again very much
on the agenda. It is important to be able to do so as soon as possible in order to prevent
the virus from spreading further. However, the techniques that are currently available do
not yield results for several hours or even days. Moreover, the tests cannot be carried
out without a laboratory or trained personnel. Researchers at Ostendum, a spin-off company
of the University of Twente, have developed a portable device that can show in five
minutes whether or not a person is infected with a particular virus. The system is able to
detect not only viruses, but also specific bacteria, proteins and DNA molecules, an
increased or reduced concentration of which in a person’s saliva may be an indication
that they have one illness or another.
Andalusian researchers find out
that postwar food vecht is an important source of antioxidant activity
Researchers of Instituto de la Grasa (part of the Spanish National Research Council -CSIC)
and the Vegetal Biology and Ecology Department of the University of Seville have found out
that vetch is an important source of phenolic compounds with a high antioxidant activity.
It is a leguminous plant of the Fabeae family, very popular during the Spanish post-war as
a basic foodstuff. Currently, vetch is frequently grown in the Indian subcontinent, in
Ethiopia and surrounding countries, in the Mediterranean area and in South America. This
finding is paradoxical because its excessive consumption causes lathyrism, a disease of
the spinal cord. It has been published in the Food Science and Technology of the Swiss
Society of Food Science and Technology journal. For researchers, these results could open
a door to future alternative growings. Polyphenols are antioxidants that protect LDL's
from oxidation. They are absorbed in our body and appear in our blood and tissues through
fruits, vegetables and wine. Its consumption causes an increase of the antioxidant
capacity in the blood, which prevents oxidative stress, linked to diseases and the ageing
process. Researchers studied the content in polyphenols and the antioxidant activity of
the seeds of 15 species of Lathyrus in Andalusia: L. hirsutus, L. filiformis, L. sativus,
L. cicera, L. angulatus, L. sphaericus, L. annuus L. clymenum, L. pratensis, L. ochrus, L.
aphaca, L. latifolius, L. setifolius, L. tingitanus and L. amphicarpos. In this research
work, scientists noticed different proportions in the contents of the seeds polyphenols,
which fluctuated between 3.8 mg/g of flour in L. setifolius and 29.2 mg/g in the case of
L. sphaericus. Moreover there were higher contents of polyphenols in the smallest seeds
due to a higher amount of husk, which is richer in these compounds.
Breastfeeding duration and weaning
diet may shape child's body composition
Variations in both milk feeding and in the weaning diet are linked to differences in
growth and development, and they have independent influences on body composition in early
childhood, according to a new study accepted for publication in The Endocrine Society's
Journal of Clinical Endocrinology & Metabolism (JCEM). Previous studies suggest that
the early environment may be a significant factor in childhood obesity. This study used
dual x-ray absorptiometry to make direct measures of body composition in children at four
years of age whose diets had been assessed when they were infants. The findings showed
that children who had been breastfed longer had a lower fat mass which could not be
explained by differences in family background or the child's height. "Most studies
linking infant feeding to later body composition focus on differences in milk feeding, but
our study also considered the influence of the weaning diet," said Dr. Siân
Robinson, PhD, of the MRC Epidemiology Resource Centre, University of Southampton in the
United Kingdom and lead author of the study. "We found that, independent of the
duration of breastfeeding, children with higher quality weaning diets including fruits,
vegetables, and home-prepared foods had a greater lean mass at four years of age."
Immunologists identify biochemical
signals that help immune cells remember how to fight infection
Immunology researchers at UT Southwestern Medical Center have discovered how two
biochemical signals play unique roles in promoting the development of a group of immune
cells employed as tactical assassins. In their initial response, these immune cells, known
as cytotoxic T lymphocytes, or CTLs, kill cells infected with pathogens. They also provide
long-term protection against pathogens by "remembering" which proteins the
pathogen makes. Targeting the ability of these CTLs to remember the pathogen is one way
vaccines protect against infection. "Until now, no innate signals have been
identified that regulate the development of memory cells," said Dr. David Farrar,
assistant professor of immunology at UT Southwestern and senior author of the study
appearing online and in a future edition of Blood. "Our study is the first to
identify the signals that promote the development of these memory cells when you first get
infected." The researchers previously showed that two molecules – interferon
alpha and another signaling protein, cytokine, or IL-12 – are needed to induce the
creation of memory cells. They also found that interferon plays a key role in
"teaching" the immune system how to fight off repeated infections of the same
virus. Dr. Farrar said the findings suggest that in order to be most effective, a vaccine
should induce the secretion of both of these innate cytokines. The immune system consists
of two components – the innate system, which provides immediate defense against
infection, and the adaptive system, whose memory cells are called into action to fight off
subsequent infections. The human immune system churns out both IL-12 and interferon alpha
in large quantities in response to a viral infection.
Mit Schwämmen Tumore bekämpfen
Die Meere beherbergen die größte Artenvielfalt der Erde. Sie sind daher auch von
Bedeutung bei der Suche nach neuen Wirkstoffen zur Arzneimittelgewinnung. Die wichtigste
Quelle stellen dabei derzeit marine Schwämme dar. Denn sie produzieren toxische
Substanzen zur Verteidigung gegen natürliche Feinde. Eine dieser Substanzen ist
Psymberin, ein Wirkstoff, der zur Tumorbekämpfung genutzt werden kann. Für die
pharmakologische Nutzung ist allerdings eine Menge notwendig, die über die natürlich
vorhandene Menge hinausgeht. Die Arbeitsgruppe von Professor Dr. Jörn Piel interessiert
sich daher für Methoden, mit denen solche Wirkstoffe unter Schonung natürlicher
Ressourcen produziert werden können. Viele der Substanzen werden von bakteriellen
Symbionten produziert. Diese konnten aber außerhalb ihres Wirtes bisher nicht kultiviert
werden. Die Bonner Forscher wandten daher einen Trick an: „Unsere Strategie beruht
darauf, Gene, die für die Produktion von Wirkstoffen verantwortlich sind, aus der
Gesamt-DNA des Schwamms zu isolieren“, erklärt Professor Piel das Vorgehen seiner
Arbeitsgruppe. „Dabei sind dann auch die Erbanlagen der Bakterien, die diese
Substanzen im Schwamm produzieren.“
Common migraine pain condition also
prevalent in cluster headache
A pain condition common in people with migraines also has a high prevalence in patients
with cluster headache, according to a study conducted by researchers at the Jefferson
Headache Center at Jefferson Hospital for Neuroscience. Approximately half of a group of
patients with cluster headaches experienced cutaneous allodynia, a condition that causes
patients to have pain as a response to normally inconspicuous sensations, according to
Michael Marmura, M.D., assistant professor of Neurology at Jefferson Medical College of
Thomas Jefferson University. The study, which was published in the Journal of Headache and
Pain, included 41 patients with either chronic or episodic cluster headaches. The
researchers tested for allodynia by brushing a gauze pad over the forehead, neck and
forearms. Patients then reported if the gauze was painful or unpleasant, or not. Twenty of
the patients experienced allodynia, with the most common site of pain being the forehead.
There were no significant differences between patients who experienced allodynia and
patients who did not. The majority of patients were using preventive medications, which is
a limitation of the study. According to Dr. Marmura, allodynia has typically been
described in migraines, but this is the largest study to date showing that allodynia
occurs in cluster headache. "It was surprising to find that allodynia was so common
in patients with cluster headaches," Dr. Marmura said. "This could have
important treatment implications, and suggests that there may be overlap in mechanisms for
pain between migraines and cluster headaches."
Legal loophole exposes Canadians to
drug advertising banned in US
A legal loophole is counteracting Canada's ban on direct-to-consumer drug advertising and
has exposed Canadians to more than $90 million worth of ads, including those for drugs
with life-threatening risks, according to a study by UBC researchers. Barbara Mintzes,
Steve Morgan and James M. Wright from UBC's Centre for Health Services and Policy Research
analyzed advertising spending on prescription drugs from 1995 to 2006 and saw spending
rise from less than $2 million per year prior to 1999 to more than $22 million in 2006.
The increase in advertising spending coincided with a policy change in 2000, when Health
Canada allowed "reminder ads" – ads that state the brand name without
additional information or health claims –under the price advertising provision in the
Food & Drug Act. This provision was created in the 1970s to allow consumers to compare
prices of prescription drugs. "This loophole is being exploited to advertise
prescription-only medicines to the Canadian public, including those with U.S. 'black-box'
warnings and those subject to Health Canada safety advisories," says Mintzes, an
assistant professor in the UBC Dept. of Anesthesiology, Pharmacology & Therapeutics.
The U.S. and New Zealand are the only two developed countries that allow
direct-to-consumer advertising (DTCA) of prescription drugs. However, the U.S. prohibits
reminder ads with a "black box" warning – the country's strongest
regulatory warning of serious harmful side effects. Canada is the only country in the
world where prescription drug advertising to the public is banned while "reminder
ads" of such drugs are allowed.
Activated stem cells in damaged
lungs could be first step toward cancer
Stem cells that respond after a severe injury in the lungs of mice may be a source of
rapidly dividing cells that lead to lung cancer, according to a team of American and
British researchers."There are chemically resistant, local-tissue stem cells in the
lung that only activate after severe injury," said Barry R. Stripp, Ph.D., professor
of medicine and cell biology at Duke University Medical Center. "Cigarette smoke
contains a host of toxic chemicals, and smoking is one factor that we anticipate would
stimulate these stem cells. Our findings demonstrate that, with severe injury, the
resulting repair response leads to large numbers of proliferating cells that are derived
from these rare stem cells." Stripp said this finding could be related to the
increased incidence of lung cancer in people with chronic disease states, in particular
among cigarette smokers. The findings were published in the advance online edition of the
Proceedings of the National Academy of Sciences during the week of May 25. "On the
positive side, I think that it might be possible to improve lung function in the context
of disease if we could understand which pathways regulate lung stem cell activation and
then target these pharmacologically," said lead author Adam Giangreco, Ph.D., from
Cancer Research UK's Cambridge Research Institute. "In terms of lung cancer
susceptibility, however, our observation that stem cell activation leads to clonal
expansion after injury could, in the context of additional mutations, promote the
development of cancerous or precancerous lesions from activated stem cells."
Is vitamin D deficiency linked to
Alzheimer's disease and vascular dementia?
There are several risk factors for the development of Alzheimer's disease and vascular
dementia. Based on an increasing number of studies linking these risk factors with Vitamin
D deficiency, an article in the current issue of the Journal of Alzheimer's Disease (May
2009) by William B. Grant, PhD of the Sunlight, Nutrition, and Health Research Center
(SUNARC) suggests that further investigation of possible direct or indirect linkages
between Vitamin D and these dementias is needed. Low serum levels of 25-hydroxyvitamin D
[25(OH)D] have been associated with increased risk for cardiovascular diseases, diabetes
mellitus, depression, dental caries, osteoporosis, and periodontal disease, all of which
are either considered risk factors for dementia or have preceded incidence of dementia. In
2008, a number of studies reported that those with higher serum 25(OH)D levels had greatly
reduced risk of incidence or death from cardiovascular diseases. Several studies have
correlated tooth loss with development of cognitive impairment and Alzheimer's disease or
vascular dementia. There are two primary ways that people lose teeth: dental caries and
periodontal disease. Both conditions are linked to low vitamin D levels, with induction of
human cathelicidin by 1,25-dihydroxyvitamin D being the mechanism. There is also
laboratory evidence for the role of vitamin D in neuroprotection and reducing
inflammation, and ample biological evidence to suggest an important role for vitamin D in
brain development and function.
PET scan can noninvasively measure
early assessment of treatment for common type of breast cancer
Non-invasive imaging can measure how well patients with the most common form of breast
cancer - estrogen receptor positive type - respond to standard aromatase inhibitor therapy
after only two weeks and shows similar findings that more invasive needle sampling
identifies, according to a poster presentation to be presented at the ASCO annual meeting
next week. Using Positron Emission Tomography (PET) scanning and a glucose analogue called
FDG, a research team led by Hannah Linden, M.D. and David Mankoff M.D., of the Seattle
Cancer Care Alliance and the University of Washington, scanned 21 patients before and
after two weeks of aromatase inhibitor therapy. Many of the patients also underwent a
needle biopsy as a control measure to compare the two techniques. The results – 16 of
the 21 patients had a greater than 20 percent decline in FDG values –
"paralleled perfectly" earlier work done by UK-based researchers who used needle
biopsies to measure whether the proliferation of cancer cells was slowed by therapy,
according to Linden, who is a breast cancer oncologist. "Our findings are exciting
because they suggest that we can measure a patient's response to therapy noninvasively,
and PET scanning provides us simultaneous quantitative metabolic measurements at multiple
tumor sites," Linden said. "PET has the potential to be a powerful tool to help
doctors make important treatment decisions in as little as two weeks instead of two or
more months."
Supermarket Discounts Promote
Unhealthy Choices
Supermarket shoppers may be encouraged to buy sugar-filled, calorie-rich drinks by
discounts and promotions, according to New Zealand research. A study, published in
Nutrition & Dietetics by Wiley-Blackwell, found healthy drinks were less likely to be
discounted in supermarkets. And the amount of the discount was greater on products higher
in fat, sugar and energy. The researchers looked at about 1,500 discounts over a month in
four supermarkets across Wellington. They found only 15 per cent of all the non-alcoholic
drinks discounted were classed as ‘healthy'. ‘Our study shows healthy drinks are
discounted less often than unhealthy drinks. But there are more unhealthy drinks available
in supermarkets and this may explain some of the difference,' said author Louise Signal
from the University of Otago. ‘Given the influence discounts can have on what
shoppers purchase, supermarkets could promote healthy options by discounting the products
that are nutritious and contain less saturated fat and added sugar' said Claire Hewat,
Chief Executive Office of the Dietitians Association of Australia (DAA). She said this
would encourage shoppers to purchase healthier choices at the supermarket and would be an
important step in addressing overweight and obesity. As part of its comprehensive obesity
strategy, DAA is calling for healthy food to be more readily available and affordable for
all Australians, tighter government regulation of food marketing, and clearer nutrition
information on food labels. Beverages classed as ‘healthy' in the study were water,
plain reduced-fat milk and plain reduced-fat soy beverages. And those in the
‘unhealthy' group included sweetened carbonated beverages, sports beverages and
flavored waters and cordial.
Some neural tube defects in mice
linked to enzyme deficiency
Women of childbearing age can reduce the risk of having a child born with a neural tube
defect such as spina bifida by eating enough folate or folic acid. However, folate
prevents only about 70 percent of these defects. New research using mice at Washington
University School of Medicine in St. Louis confirms the importance of another nutrient,
inositol, to protect against the development of neural tube defects. A research team led
by Monita Wilson, Ph.D., found neural tube defects in some mouse embryos from female mice
genetically modified to have low levels of ITPK1, an enzyme involved in the metabolism of
inositol, a compound important for neural development and function. The finding suggests
that inositol depletion is linked to these birth defects. The research is published May 25
in the Proceedings of the National Academy of Sciences Early Edition. In humans, neural
tube defects usually occur during the first three to four weeks of pregnancy, before most
women know they are pregnant. Certain cells in an embryo form the neural tube, which
becomes the foundation of the brain, spinal cord and the bone and tissue surrounding it. A
defect forms if the tube does not close properly. The two most common neural tube defects
are spina bifida and anencephaly. Spina bifida affects 1,500 to 2,000 babies born in the
United States annually, causing paralysis, spine abnormalities, incontinence and other
problems. Anencephaly occurs when the head end of the neural tube fails to close,
resulting in the absence of a major portion of the brain, skull and scalp. That condition
is fatal. Wilson, research assistant professor of medicine, and her collaborators created
genetically modified mice to have low levels of one of the inositol kinases, then took a
close look at their embryos during each day of the 21-day gestation period. "Because
of the short gestation period, a mouse embryo looks very, very different from day to
day," Wilson says. "When we looked at the mutant embryos, between the ninth and
12th days of gestation, we noticed that about 12 percent to 15 percent had spina bifida
and exencephaly, similar to anencephaly in humans."
Survey suggests higher risk of
falls due to dizziness in middle-aged and older Americans
A full third of American adults, 69 million men and women over age 40, are up to 12 times
more likely to have a serious fall because they have some form of inner-ear dysfunction
that throws them off balance and makes them dizzy, according to Johns Hopkins experts.
Among the other key findings of the three-year survey and study on the subject by the
Johns Hopkins team are that a third of this group, or more than 22 million, were unaware
of their vulnerability, having had no previous incidents of disequilibrium or sudden falls
to suggest that anything was wrong. In the survey, to be published in the Archives of
Internal Medicine online May 25, these asymptomatic people were three times more likely to
suffer a potentially fatal fall than people with a healthy sense of balance, whereas
people already experiencing symptoms of imbalance had a 12-fold increase in risk.
Accidental falls are among the leading causes of death in the elderly, killing an
estimated 13,000 seniors each year in the United States and resulting in more than one and
a half million visits to hospital emergency rooms, experts say. "Vestibular
imbalances need to be taken seriously because falls can be fatal and injuries can be
painful, lead to long hospital stays and result in significant loss in quality of
life," says Lloyd B. Minor, M.D., the Andelot Professor and director of
otolaryngology – head and neck surgery at the Johns Hopkins University School of
Medicine. Minor says that recent government reports estimate that fatal falls in the
elderly cost the U.S. Medicare program nearly $1 billion in hospital charges, and those
injured with broken bones cost an additional $19 billion. More than 5,000 men and women
over age 40 participated in the survey, which took three years to complete and involved
specialized exams and balance testing to find out who had vestibular dysfunction, its
early signs and symptoms, and who did not.
Nervous system may be culprit in
deadly muscle disease
Brain may win out over brawn as the primary cause of breathing problems in children with a
severe form of muscular dystrophy known as Pompe disease. Researchers at the Powell Gene
Therapy Center at the University of Florida have discovered that signals from the brain to
the diaphragm — the muscle that controls breathing — are too weak to initiate
healthy respiration in mouse models of the disease. The discovery for the first time
shifts responsibility to the nervous system for the severe breathing problems experienced
by infants with Pompe disease, a rare genetic disorder that causes extreme muscle
weakness. Children born with the disorder usually die before age 2. "For years what
we have thought is principally a muscle disease may actually be caused by problems with
signaling between the spinal cord and the muscle," said Dr. Barry Byrne, a UF
pediatric cardiologist, a member of the UF Genetics Institute and the director of the
Powell Gene Therapy Center. "As we've treated children with this disease, we found
many of them have become ventilator-dependent, so we went back to the laboratory and found
that a significant part of the respiratory deficit is in the spinal cord and not in the
diaphragm alone." The findings, which will be published the week of May 25 in the
online early edition of the Proceedings of the National Academy of Sciences, also have a
bearing on motor neuron diseases, a group of incurable brain disorders that destroy cells
that influence essential muscle activity such as speaking, walking, breathing and
swallowing. Notable among these is ALS, technically known as amyotrophic lateral sclerosis
or, more commonly, Lou Gehrig's disease. Although many laboratory discoveries never
advance to the point where they can be confirmed in patients, scientists will be able to
evaluate whether there is indeed a neural aspect to Pompe disease in a clinical safety
study of a gene therapy in six infants with the disorder. The clinical trial, which will
begin this summer at UF, had previously advanced on its merits as a therapy for breathing
problems in a group of patients who have very few treatment alternatives. Children with
Pompe disease cannot produce the enzyme acid alpha-glucosidase, or GAA. Without the
enzyme, sugars and starches that are stored in the body as glycogen accumulate and destroy
muscle cells, particularly those of the heart and respiratory muscles.
Cordoba-based researchers
transplant stem cells from the marrow into the heart to improve its performance
The Cardiology department and the Area of Cell Therapy of Cordoba hospital Reina Sofia are
carrying out clinical tests with patients who have suffered from a severe heart attack.
With the implantation of the patient's stem cells, the heart regenerates thus improving
its wall motion, that is, its cardiac performance. This work, published in the prestigious
Revista Española de Cardiología journal, has been awarded with a prize by the Sociedad
Española de Cardiología. Indeed for the last four years, the Area of Cell Therapy of
Cordoba hospital, led by haematologist Dr. Concha Herrera, has been implementing a therapy
program with adult stem cells in patients with heart-related problems. However, this
therapy is not a service the hospital offers yet. More specifically, at the end of 2007
the hospital ended a clinical test with patients who had suffered a severe myocardial
infarction, that is, an obstruction of one of the main coronary arteries that stops the
blood pump to the heart. The test consisted of treating 30 people split into three groups
of ten each at random. The first group was the control group, where patients received
standard treatment for acute myocardial infarction; the second group was treated with stem
cells directly implanted into the coronary artery affected using a catheterization; the
third group was treated with a medicine called G-CSF, which makes cells move from the
marrow to the blood, so that they get to the heart in a natural way, without having to do
so through a catheter. At the end of the test, the results revealed that the two groups
treated without cells improved slightly, whereas patients transplanted with stem cells
through the coronary arteries (vessels which bring the blood to the Herat muscle) did
improve their ventricular function much more. This was interpreted as a significant
decrease of the cardiac failure symptoms such as pain, fatigue and breathlessness when
making small efforts.
Salmonella and self-sacrifice
Our large intestines are heavily populated by bacteria and as such really do not have
space for newcomers. Despite this, Salmonella are able to multiply there. In a project
funded by the Swiss National Science Foundation, a group led by Wolf-Dietrich Hardt from
ETH Zurich is uncovering the remarkable strategies used by the feared diarrhoea pathogens.
A small number of the Salmonella sacrifice themselves by attacking the intestinal cells.
Although this kills them, they succeed in causing inflammation. The inflamed intestine
excretes mucus, which ultimately accelerates the growth of the remaining salmonella in the
intestine. Thus the bacteria benefit from the death of their sister cells. Salmonella
(red) have to prevail against the intestinal flora (small green dashes).
Australian team reveals world-first
discovery in a 'floppy baby' syndrome
In a world first, West Australian scientists have cured mice of a devastating muscle
disease that causes a Floppy Baby Syndrome – a breakthrough that could ultimately
help thousands of families across the globe. The research, published online today in the
Journal of Cell Biology, reveals how a team at the Western Australian Institute for
Medical Research (WAIMR) has restored muscle function in mice with one type of Floppy Baby
Syndrome – a congenital myopathy disorder that causes babies to be born without the
ability to properly use their muscles. The currently incurable genetic diseases render
most of the affected children severely paralysed and take the lives of the majority of
these children before the age of one. Dr Kristen Nowak, lead author on the publication,
said the team was extremely encouraged that it had been able to cure a group of mice born
with the condition. "The mice with Floppy Baby Syndrome were only expected to live
for about nine days, but we managed to cure them so they were born with normal muscle
function, allowing them to live naturally and very actively into old age," she said.
"This is an important step towards one day hopefully being able to better the lives
of human patients – mice who were cured of the disease lived more than two years,
which is very old age for a mouse." Dr Nowak said the team was able to cure the mice
with the recessive form of the genetic condition by replacing missing skeletal muscle
actin – a protein integral in allowing muscles to contract – with similar actin
found in the heart. "Earlier in our search to tackle these diseases, we discovered a
number of children who, despite having no skeletal muscle actin in their skeletal muscle
due to their genetic mutation, were not totally paralysed at birth," she said.
"On closer inspection, we found it was because heart actin – another form of the
protein – was abnormally "switched on" in their skeletal muscles. "We
had already begun investigating whether we could use heart actin to treat skeletal muscle
actin disease, so that discovery spurred us on, and we've now proved it can be done –
we can use heart actin to overcome the absence of skeletal muscle actin in mice."
Heart actin is found in cardiac muscle and, during foetal development, it also works in
skeletal muscles in the body, but by birth, heart actin has almost completely disappeared
within skeletal muscle. Using genetic techniques, the WAIMR research team has reactivated
the heart actin after birth in place of skeletal muscle actin, reversing the effects of
the congenital myopathy.Head of the WAIMR research group Professor Nigel Laing said the
team's next step was to apply their findings to human patients. "We are now screening
more than a thousand already-approved medications looking for one that might increase
heart actin in skeletal muscles, which could potentially offer a treatment for many
patients," he said. "Current therapies only target the effects of these
conditions, not the condition itself – we hope our approach could lead to a much
greater improvement for a range of muscle diseases." This discovery is the latest for
the team which has been investigating debilitating muscle diseases for more than 20 years.
Stronger material for filling
dental cavities has ingredients from human body
ulian X.X. Zhu and colleagues point out that dentists increasingly are using white
fillings made from plastic, rather than "silver" dental fillings. Those
traditional fillings contain mercury, which has raised health concerns among some
consumers and environmental issues in its production. However, many plastic fillings
contain controversial ingredients (such as BisGMA) linked to premature cracking of
fillings and slowly release bisphenol A, a substance considered as potentially toxic to
humans and to the environment. The scientists developed a dental composite that does not
contain these ingredients. Instead, it uses "bile acids," natural substances
produced by the liver and stored in the gallbladder that help digest fats. The researchers
showed in laboratory studies that the bile acid-derived resins form a hard, durable
plastic that resists cracking better than existing composites.
Long-forgotten research may yield
new malaria treatments
An unlikely friendship between a 94-year-old retired scientist and a biochemist at Rutgers
University has lead to the revival of a World War II-era research program to develop new
drugs against malaria, the deadly mosquito-borne disease that kills almost one million
people annually, according to an article scheduled for the May 25 issue of Chemical &
Engineering News, ACS' weekly newsmagazine. C&EN senior editor Lisa Jarvis explains in
the article that existing anti-malaria drugs are losing effectiveness as the parasite
responsible for the disease develops resistance. The article describes how the retired
Merck researcher provided a long forgotten 1947 research paper detailing the company's
early efforts to identify and test tropical plants that might fight malaria. Though the
paper described some 600 plants that showed promise against the disease, scientists never
pursued a more rigorous program to study the plants. Armed with public and private
funding, a biochemist at Rutgers is now resurrecting this research project. University
scientists have already identified 60 promising plants from the group and found at least
10 active substances that could be turned into promising drugs. Chemists will eventually
try to make the most active substances more potent, last longer, and minimize their
side-effects, the article notes.
Heart saves muscle
A heart muscle protein can replace its missing skeletal muscle counterpart to give mice
with myopathy a long and active life, show Nowak et al. The findings will be published
online on Monday, May 25, 2009 (www.jcb.org) and will appear in the June 1, 2009 print
issue of the Journal of Cell Biology. The contraction machinery protein, actin, exists in
different forms in the adult heart and skeletal muscles. The heart form, ACTC, is also the
dominant form in skeletal muscle of the fetus. But during development, the skeletal form,
ACTA1, increases in production and by birth has taken over. It is not clear why the switch
occurs, or why it doesn't occur in the heart, but it happens in every higher vertebrate
and, for that reason, has been considered vitally important. Mutations to the ACTA1 gene
cause a rare but serious myopathy. Most patients die within the first year of life and
some are born almost completely paralyzed. Mice lacking ACTA1 die nine days after birth.
Nowak et al. wondered if ACTC could compensate for a lack of ACTA1. The two proteins
differ only slightly but, like the developmental switch in production, this difference is
conserved across species. Many researchers therefore assumed such compensation would never
work. But it did. Nowak and colleagues crossed Acta1 mutant mice with transgenic mice that
express human ACTC at high levels in skeletal muscle cells. The resulting mice didn't die
at nine days. In fact, almost all of them (93.5%) survived more than three months, and
some more than two years. The mice's locomotor performance was comparable with wild-type,
as was their overall muscle strength (though individual muscle fibers were slightly
weaker), and their endurance was actually higher—they ran faster and for longer.
Study indicates people by nature
are universally optimistic
Despite calamities from economic recessions, wars and famine to a flu epidemic afflicting
the Earth, a new study from the University of Kansas and Gallup indicates that humans are
by nature optimistic. The study, to be presented Sunday, May 24, 2009, at the annual
meeting of the Association for Psychological Science in San Francisco, found optimism to
be universal and borderless. Data from the Gallup World Poll drove the findings, with
adults in more than 140 countries providing a representative sample of 95 percent of the
world's population. The sample included more than 150,000 adults. Eighty-nine percent of
individuals worldwide expect the next five years to be as good or better than their
current life, and 95 percent of individuals expected their life in five years to be as
good or better than their life was five years ago. "These results provide compelling
evidence that optimism is a universal phenomenon," said Matthew Gallagher, a
psychology doctoral candidate at the University of Kansas and lead researcher of the
study.
Opposites attract -- how genetics
influences humans to choose their mates
New light has been thrown on how humans choose their partners, a scientist will tell the
annual conference of the European Society of Human Genetics today (Monday May 25).
Professor Maria da Graça Bicalho, head of the Immunogenetics and Histocompatibility
Laboratory at the University of Parana, Brazil, says that her research had shown that
people with diverse major histocompatibility complexes (MHCs) were more likely to choose
each other as mates than those whose MHCs were similar, and that this was likely to be an
evolutionary strategy to ensure healthy reproduction. Females' preference for MHC
dissimilar mates has been shown in many vertebrate species, including humans, and it is
also known that MHC influences mating selection by preferences for particular body odours.
The Brazilian team has been working in this field since 1998, and decided to investigate
mate selection in the Brazilian population, while trying to uncover the biological
significance of MHC diversity. The scientists studied MHC data from 90 married couples,
and compared them with 152 randomly-generated control couples. They counted the number of
MHC dissimilarities among those who were real couples, and compared them with those in the
randomly-generated 'virtual couples'. "If MHC genes did not influence mate
selection", says Professor Bicalho, "we would have expected to see similar
results from both sets of couples. But we found that the real partners had significantly
more MHC dissimilarities than we could have expected to find simply by chance."
Within MHC-dissimilar couples the partners will be genetically different, and such a
pattern of mate choice decreases the danger of endogamy (mating among relatives) and
increases the genetic variability of offspring. Genetic variability is known to be an
advantage for offspring, and the MHC effect could be an evolutionary strategy underlying
incest avoidance in humans and also improving the efficiency of the immune system, the
scientists say.
UCD researchers reveal six new
genome sequences and fundamental insights to the Candida fungus family
An international research collaboration coordinated by UCD researchers and involving
scientists at 21 institutes including the genome sequencing centres in the Wellcome Trust
Sanger Institute, UK and the Broad Institute at MIT and Harvard, USA have defined six new
genome sequences in the Candida fungus family and identified genetic differences in
species that cause disease. The research, published yesterday in Nature, describes how
Candida strains have evolved and ensured their survival by adapting their genetic makeup
to respond to changes in their environment. Candida species are the most common cause of
opportunistic fungal infection worldwide. The incidence of Candida parapsilosis in
particular poses the greatest threat to transplant patients and premature babies as it
forms a film that coats the inside of medical devices such as implants, catheters or
feeding tubes. The fungus is drug resistant and the only effective treatment involves the
removal of the medical device. Prior to this work, very little was known about this
species. The UCD research team led by Professor Geraldine Butler from UCD Conway Institute
& School of Biomolecular & Biomedical Science looked at key components of mating
and cell division in Candida species, shedding new light on how the fungi reproduce and
survive. Professor Butler, scientific coordinator on this project, began working to
identify the sequence of genes of C. parapsilosis in 2003 through funding from Science
Foundation Ireland. She said, “We started by sequencing small parts of the C.
parapsilosis genome, which led to our collaboration with the Sanger Institute to sequence
the entire genome, and finally to combining this genome with others sequenced by the Broad
Institute”
An efficient approach to monitor
gastrointestinal microflora changes
Pi-deficiency in traditional Chinese medicine (TCM) is one of the most common digestive
diseases and usually the equilibrium of gastrointestinal microflora are broken, which
plays many important roles in the growth, development and performance of the host.
Therefore, more clinical interests are arising in monitoring changes of intestinal
microflora in intestinal disease and the consequent treatment, especially in TCM
therapies. It has been found that some Chinese materia medica have curative effects on
regulating the equilibrium of intestinal microflora and therefore promote the recovery of
'Pi'. However, ways of monitoring the intestinal flora are quite limited, not only because
of the complexity of its constitution, but also the difficulty of culturing for most
gastrointestinal bacteria in vitro. A research article to be published on May 14, 2009 in
the World Journal of Gastroenterology addresses this question. The research team led by
Prof. Li from School of Pharmacy of Shanghai Jiao Tong University, China, used
enterobacterial repetitive intergenic consensus-PCR (ERIC-PCR), which is a PCR-based
molecular method, and utilizes oligonuleotides targeting short repetitive sequences ERIC
which are dispersed throughout various bacterial genomes, to study changes of intestinal
microflora under Pi-deficiency state and evaluate therapeutic effects of Chinese materia
medica. ERIC-PCR have implications in monitoring the effects of various known factors on
the complex intestinal microflora community. The article introduced it to examine the
changes of intestinal mircoflora of Pi-deficiency disorder with two animal models. They
further evaluate the efficacy of four Chinese materia medicas as well as a probiotic and
another disease therapy recipe in Pi-deficient rats, and determine if it could be utilized
as an initial screening of changes of the composition of bacterial communities.
New model suggests role of low
vitamin D in cancer development
In studying the preventive effects of vitamin D, researchers at the Moores Cancer Center
at the University of California, San Diego, have proposed a new model of cancer
development that hinges on a loss of cancer cells' ability to stick together. The model,
dubbed DINOMIT, differs substantially from the current model of cancer development, which
suggests genetic mutations as the earliest driving forces behind cancer. "The first
event in cancer is loss of communication among cells due to, among other things, low
vitamin D and calcium levels," said epidemiologist Cedric Garland, DrPH, professor of
family and preventive medicine at the UC San Diego School of Medicine, who led the work.
"In this new model, we propose that this loss may play a key role in cancer by
disrupting the communication between cells that is essential to healthy cell turnover,
allowing more aggressive cancer cells to take over."Reporting online May 22, 2009 in
the Annals of Epidemiology, Garland suggests that such cellular disruption could account
for the earliest stages of many cancers. He said that previous theories linking vitamin D
to certain cancers have been tested and confirmed in more than 200 epidemiological
studies, and understanding of its physiological basis stems from more than 2,500
laboratory studies. "Competition and natural selection among disjoined cells within a
tissue compartment, such as might occur in the breast's terminal ductal lobular unit, for
example, are the engine of cancer," Garland said. "The DINOMIT model provides
new avenues for preventing and improving the success of cancer treatment." Garland
went on to explain that each letter in DINOMIT stands for a different phase of cancer
development. "D" stands for disjunction, or loss of intercellular communication;
"I," for initiation, where genetic mutations begin to play a role; "N"
for natural selection of the fastest-reproducing cancer cells; "O" for
overgrowth of cells; "M" for metastasis, when cancer cells migrate to other
tissues, where cancer can kill; "I" refers to involution, and "T" for
transition, both dormant states that may occur in cancer and potentially be driven by
replacing vitamin D. While there is not yet definitive scientific proof, Garland suggests
that much of the evolutionary process in cancer could be arrested at the outset by
maintaining vitamin D adequacy. "Vitamin D may halt the first stage of the cancer
process by re-establishing intercellular junctions in malignancies having an intact
vitamin D receptor," he said. According to Garland, other scientists have found that
the cells adhere to one another in tissue with adequate vitamin D, acting as mature
epithelial cells. Without enough vitamin D, they may lose this stickiness along with their
identity as differentiated cells, and revert to a stem cell-like state. Garland said that
diet and supplements can restore appropriate vitamin D levels, and perhaps help in
preventing cancer development. "Vitamin D levels can be increased by modest
supplementation with vitamin D3 in the range of 2000 IU/day," he noted.
More effective Cancer Treatment and
the Migration of Modern Man from Africa to Western Eurasia
The Collaborative Research Centre 806 “Unser Weg nach Europa -
Kultur-Umwelt-Interaktion und menschliche Mobilität im Späten Quartär” (Our Road
to Europe - Culture-Environment-Interaction and human Mobility in the late Quaternary)
will be directed by Professor Dr. Jürgen of the Department of Pre- and Protohistoric
Archaeology. This research centre is looking at the mobility of populations in the last
190,000 years. The focus of research will be the journey of modern man from Africa to
Western Eurasia and Europe, in particular. Migration processes, and the exchange of ideas,
technology and culture that entails, are an important prerequisite for important
developments. The centre’s main aim is to research, using scientific and
archaeological methods, how human behaviour, the climate and the environment influenced
important population movements. The scientists particularly want to examine the impacts
that these factors have had on the actions and reactions of populations such as
emigration, immigration and adaptation to new environments. Other universities and
institutions are also involved the project. These include: the University of Bonn; RWTH
Aachen University; Heidelberg University; the University of Duisburg-Essen as well as the
Rhineland Regional Council; the Rheinisches Amt für Bodendenkmalpflege (Rheinland
Department for the Preservation and Care of Field Monuments) as well as the Neanderthal
Museum in Mettmann.
Sexually Transmitted HPV Linked to
Certain Head & Neck Cancers
Researchers at Roswell Park Cancer Institute (RPCI) in Buffalo, New York, are strongly
advocating a national discussion about the need to vaccinate both young men and women
against HPV 16 to prevent head & neck cancers. The call comes amid growing evidence
that certain cancers of the head and neck are strongly linked to HPV 16, a specific strain
of the human papillomavirus (HPV) that is one of the most common sexually transmitted
diseases in the United States. It is estimated that approximately 70% of Americans, both
men and women, will be infected with HPV at some point in their lives. The types of cancer
associated with HPV 16 occur mostly at the back (base) of the tongue, in the tonsils, and
in the soft palate at the back of the throat, according to Thom Loree, MD, Chair of
RPCI’s Department of Head & Neck Surgery. Over the past 10 years, members of
RPCI’s Head & Neck Department have seen a threefold increase in the number of
throat cancers they treat. In 2007, Roswell Park researchers began testing all head and
neck tumors treated at the Buffalo-based comprehensive cancer center for the presence of
HPV DNA, says Saurin Popat, MD, FRCSC, FACS, Attending Surgeon in Head & Neck and
Plastic & Reconstructive Surgery, RPCI. RPCI is one of few institutions in the nation
to do so. Data from the ongoing testing have been combined with data from archived tumor
samples to provide a clearer picture of how many head and neck cancers treated at RPCI
test positive for HPV. To date, the total is around 50 to 60 percent.There are more than
100 types of HPV—each identified by number—but only 70 have been described so
far, explains Popat. Some HPV viruses, including 16 and 18, are transmitted
sexually—not just through sexual intercourse, but through any skin-to-skin contact
involving the mouth, vagina, vulva (the external female genitalia), penis, anus, or
fingers.
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